Priming means for internal-combustion engines



Oct. 15, 1929. c, MAHANA 1,731,430

PRIMING MEANS FOR INTERNAL COMBUSTION ENGINES Filed Jan. 20, 1927 lllllllllllllll f INVENTOR ATTORNEY Patented Oct. 15, 1929 UNITED s'ra'res PATENT orrlca CHARLES Gr. MAI-IANA, OF THREE RIVERS.

MICE

EGAN, ASSIGNOB TO FAIRBANKS,

MORSE & 00., OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS PRIMING MEANS FOB. INTEBNAL-COMBUSTION ENGINES Application filed January 20, 1927. Serial No.

This invention relates to improvements in internal combustion engines and more particularly to improvements in priming means i A further object is to provide a means for delivering a priming charge of fuel through a more direct path to the cylinder than is provided by the usual carburetor and its connections.

Further objects and advantages of my device will appear from the drawings and the following detailed description thereof.

A structure which embodies this invention in executional'example is clearly illustrated in the accompanying drawing, forming a part of this specification, in which Fig. 1 is a sec tional elevation of a portion of the usual type of two-cycle engine cylinder, showing cliagrammatically the relation of the various parts essential to my idea. Figs. 2 and 3 are vertical sectional views of carburetors of conventional type showing respectively different modifications of the liquid fuel collecting arrangement.

Referring by numerals to the drawings, 1 indicates a sump in the air inlet passage 2 o the carburetor. .This sump 1 may be made in a variety of forms besides those shown in Figs. 1, 2, and 3, respectively; the essence of this feature being that it shall provide a fuel collecting pocket, regardless of shape, in

substantially the location shown with respect to the air inlet passage 2, and preferably near the carburetor float chamber 8, for a purpose which will appear later. The exact dimensions and location of sump 1 may be varied within substantial. limits, but such a sump is preferably located within the carburetor base 8, as shown. Connected to sump 1 is a tube 4:, preferably of seamless copper, brass or other metal or substance having the requisite flexibility and capacity. The end connection into the 1 therein as shown.

on tube 4 may be threaded directly carburetor base 3, and into the sump The opposite end of tube 4 is provided with a usual threaded or flanged connection with a check valve 5. Sump 1 is thus in communication through tube 4: and

check valve 5 with a cylinder by-pass 6. By-- pass 6 preferably communicates in the usual with the cylinder 7 The time of opening of by-pass 6 into cylinder 7 is determine In the various modifications,

din the example shown by a piston 10. the sump 1 may be formed in part or entirely by a retaining ridge 12, as shown in Fig. 1.

This ridge 12 serves the purpose of a dam or retaining wall on serves e one side of the inlet to tube 4, and liectively to retain a small amount of gasoline or liquid fuel in the reservoir thus rovide pllshed taming in Fig.

taining retaining ridge ment shown in stantially the sort shown in Fig. 3

provide In operation,

drawn d. The same purpose may be accomanother Way as indicated by the regroove 13 in the modification shown 2.' The effect and purpose of the regroove 13 is identical with that of 12. In lieu of the arrange Figs. 1 and 2, a sump of submay be d.

fuel for priming purposes is by engine suction from sump 1,

through tube 4, thence through check valve 5 and into the cylinder by-pass 6. The purpose of check valve 5 is that of any usual nonreturn valve so that communication is established b etween cylinder by-pass 6 and sump 1 only, during a, tlme when the pressure in bypass 6 is less than atmospheric. In lay-pass 6 the liquid fuel is picked up the air carried into the cylinder.

by mixing with the by-pass and 1s entering through The affords a comparatively rich priming charge, which suffices the car raislng put the motor in operation even under the Liquid flooding buretor, which is accomplished by the level of the fuel in float chamber 8 until it over-flows through the fuel nozzle 9 1nto the air 1nlet passage or mixing chamber 2 whereln sump 1 is located. When the engine is cranked, manually or automatically,

the suction produced within the engine draws fuel from the sump 1 into the cylinder by Way of bypass 6, thus providing an immediate priming charge for easy starting.

A type of engine to which my device is particularly applicable, has the carburetor connected directly into the crank case (not shown). During the normal operation of such an engine the path of fuel is from the carburetor into the crank case, thence through the bypass and to the cylinder. My invention provides'amuch shorter, less circuitous path for the priming charge, by its introduction directly to the bypass at a point near the cylinder.

In the illustrated example, I have shown this device as applied to a twocycle engine. Obviously, I Wish it understood that a similar arrangement of parts may be employed with only slight 'mo difications to serve the same purpose"when'applied to a four-cycle engine, or to any other internal combustion engine using an external mixing device for liquid fuel.

WVhat I claim is:

1. In a two-cycle internal combustion ongine having a cylinder, a piston operating therein, a pressure crank case and a by-pass conduit between the crank case and cylinder, the combination of a carburetor, having a body portion comprising a float chamber, an air inlet portion. and'a fuel sump formed in the air inlet portion and adapted to receive fuel from the float chamber during the period ofstarting the engine,'a liquid fuel tubeof restricted diameter having one terminus in said sump and the other terminus in the bypass conduit and so disposed as to deliver fuel by gravity, substantially to the delivery end of the conduit; means forming a cylinder port for the introduction of both running fuel and starting fuel from said tube, directly to the c'ylin'der, said fuel tube bein arranged to provide a fuel path to the cylinde ',for priming, substantially shorter than the normal path of fuel mir-rturc during running of the engine, and a check valveat the delivery end of the by-p'ass conduit.

2. In a two-cycle internal combustion engine having a cylinder, a piston therein, a pressure crank cascand a by-pass conduit between the crank case and cylinder, the combination of a carburetor arranged to deliver fuel mixture to said crank case, the carburetor having a body portion comprising a float chamber, an air inlet passage and a fuel sump or reservoir formed in the airinlet passage, and adapted'to receive'fuel directly from the float chamber during the period of starting the engine, said sump being in the path of the intake air normally admitted to the carburetor ali uid fuel tube of restricted diameter adapted for :direct communication between said sump or reservoir and a point in the by pass conduit substantially at, and directly above, the delivery end of the conduit; means iii 

